查询词典 parameter estimation

In chapter 5,a knowledge-based correction term for the objective function of parameter estimation is proposed.The relationship between the function extreme points of state estimatin and parameter estimation is deduced.A strategy of projecting the parameter objective function from the augmented solution space to the parameter space is proposed and proved.

第五章分析了电力系统状态估计和参数估计的理论依据并指出传统解法的不足，提出基于经验知识的参数估计目标函数修正项，推导了状态估计和参数估计目标函数极值点的关系，由此提出并证明了新的基于垂直投影的估计策略。

The main job and contribution of this paper are as follows:Based on narrowband signal processing, we propose a new method for FH signal blind detection and blind parameter estimation. Firstly, compute the cross-correlation function of FH signals from multichannels, then we get the cross power spectral density matrixCSDM Secondly, select the hops of FH signals from the CSDM via processing and analyzing the CSDM, meanwhile reduce the influence coming from noise, fixed frequency signal and other interferences; Lastly, estimating the DOA of every hop and according to the DOA, we can separate the hops, get the number of FH signals and their parameters. Propose a new method for designing the threshold in FH signal detection. This method makes it easy to get the threshold by theoretic computing and it can extremely reduce the interference of non-FH signals.Based on broadband signal processing, we propose a new method for FH signal blind detection and blind parameter estimation. Firstly, get the DOA of the signals by wideband spatial spectrum estimation; secondly, separate the signals by spatial filtering using wideband beamformer; Lastly, we propose two methods for FH signal blind detection and blind parameter estimation, one is for several constant hop-rate FH signals whose dwell-time are different and another is for a single FH signal whose hop-rate is alterable.By employing spatial interpolation in broadband signal beamforming, it can reduce the number of antenna elements and corresponding RF modules, A/D converters, etc. It can also eliminate the mutual coupling between antenna elements while getting the narrower main beamwidth and lower sidelobe level.

本文的主要研究工作和贡献如下：●提出了一种基于窄带处理的FH信号盲检测和参数盲估计的实现方法，即首先求出多路信号之间的互相关，进而得到互功率谱密度矩阵，然后通过对CSDM进行对折处理来抑制噪声、定频信号及其他干扰的影响，并将所有属于FH信号的hop(每一跳的驻留时间在时频图上持续的线段)从CSDM中筛选出来，最后用阵列信号处理中的到达方向估计理论在频域中估计出各个hop的方向参数，利用方位信息完成FH信号分离并得到FH信号的数目及其各自的参数集；●提出了一种确定FH信号检测门限的策略，该策略不仅使得检测门限能够通过理论计算得到，而且还显著地抑制了非跳频信号的干扰，从而能有效地检测出FH信号；●提出了一种基于宽带处理的短波FH信号盲检测和参数盲估计的实现方法，即首先利用宽带空间谱测向技术得到接收信号的DOA，然后采用宽带波束形成技术对特定方向进行空间滤波，实现多个信号的分离，最后分别提出了两种FH信号的盲检测和参数盲估计方法，第一种方法适用于空间某个特定方向上存在着几个驻留时间不同的恒跳速FH信号和其他干扰信号的混合信号，第二种方法适用于空间某个特定方向上仅含一个可变跳速的FH信号和噪声的混合信号；●将空间插值的概念和宽带波束形成技术结合起来，提出了一种基于频域处理的宽带恒定束宽的波束形成方法。

Time-Frequency parameter estimation and direction finding for nonstationary signals impinging on an antenna array over a wide frequency band (2~18GHz) is under in-vestigation, and a new method for parameter and 2-D Angle-Of-Arrival estimation of spatio-temporal undersampled LFM sources is proposed in this paper.

摘要针对宽频段(2-18GHz)内非平稳来波信号的参数估计和测向问题，提出一种时空欠采样线性调频信号参数与二维到达角联合估计方法。

First, mathematical foundation of synchronization, i.e. the theory of parameter estimation is introduced. Then, DA/DD or NDA timing synchronization methods based on the ML estimation of timing parameter are presented. They are all widely applied in actual digital communication systems. Interpolation theory in digital signal processing has application in timing synchronization, which makes the sampling clock independent of the timing control so that timing adjustment is realized completely through digital disposal. The issue of interpolation in timing synchronization is discussed.

首先，介绍了定时同步实现的数学基础，即信号参数估计理论；从定时参数的最大似然估计出发，介绍了基于数据辅助的定时同步方法和基于非数据辅助的定时同步方法，他们在实际的数字通信系统中均有广泛应用；论文探讨了数字信号处理中插值理论在定时同步中的应用，它使得接收端的采样时钟独立于定时控制，定时调整完全通过数字处理方法得以实现。

The thesis analyzes the methods for parameter estimation of distributed sources in detail, and low complexity estimators, comes up with RELAX in parameter estimation and robust method of high resolution parameter estimators for distributed sources, and gives theory analysis and simulation results. The main work is:1 This text gives a study of the signal models of two kinds of distributed sources: coherent distributed sources and incoherent distributed sources, analyzes eigenvalue distribution of correlation matrix.2 Systematically introduced parameter estimation of distributed sources on the base of models, including the maximum likelihood estimate, least squares estimator, DSPE, DISPARE, etc.

论文详细分析了已有分布式目标参数估计方法及低复杂度的参数估计方法，提出了分布式目标参数估计的RELAX算法和具有稳健性的分布式目标高分辨估计方法，并给出了相应的理论分析和仿真实验结果。

Experimental results show that the performance of local parameter estimation is superior to that of global parameter estimation when there are no attacks, and the performance of local parameter estimation is worse than that of global parameter estimation when there are attacks.

通过实验得到以下结论：在无攻击条件下，局部参数估计的性能优于整体参数估计的性能；在有攻击条件下，整体估计的性能要好于局部参数估计的性能；压缩攻击会导致水印误检概率的增加，不同的攻击对模型造成的影响不同。

In the parameter estimation of the probability of default model,nonrandom sample selection will cause sample selec- tion bias and bring biased parameter estimation.

在贷款违约概率模型的参数估计过程中，样本选择的非随机性会产生样本选择性偏差，导致参数估计有偏。

Based on the least square criteria and to ensure the convergence of kinetic parameter estimation, we suggested a weighted Levenberg-Marquardt algorithm which introduces a relaxation parameter to prevent estimation procedure from divergence.

本研究除了沿用LM以残差平方总合作为调整修正步伐的方法外，另外还考量动态参数个别收敛的情况。

Estimations of effective parameter in heterogeneous media: Firstly, we clarify the concept of the effective parameter and address the problems of parameter estimation by traditional pumping test. Secondly, we present two estimation approaches (i.e., distance-drawdown and spatial moment analyses) for Seff and Teff, which are consistent with Theis' homogeneous aquifer assumption.

本文探讨的内容主要分两大部分：(1)空间异质性孔隙介质有效参数的推估方法：主要探讨内容包括重新思考有效参数的定义及其观念，探讨传统抽水试验推估异质性含水层有效参数的一些问题，其次提出估计异质性地下水系统有效参数两个合理方法：泄降-距离曲线分析和泄降分布的空间矩分析，并以数值实例解释其合理性，文中藉由分析数值模拟的结果探讨说明该问题。

Combined GIS with MATLAB, the automatic extraction of RS and geography information of sample plots was realized.5. Introduced the resist-PCA estimation method to build the estimation formula on crown density, stock volume and diameter breast height, good forecast accuracy was achieved and the deficiency of traditional LMS parameter estimation was made up.6. The estimation process software of the model was developed, including data pretreatment, weight function selection, LMS estimation, PCS estimation, resist-PCA estimation, accuracy assessment and other function models, in order to c

摘要4、结合Gls和MATLAB技术实现对样地遥感信息和地理环境信息的自动提取。5、引入抗差主成分估计方法建立郁闭度、蓄积量、胸径的估测方程，取得了良好的估测精度，弥补了传统最小二乘参数估计的不足。6、开发了模型估测处理软件，包括数据预处理、权函数选择，LS估计，主成分估计、抗差主成分估计、精度评价等模块，实现数据处理、模型研建与精度评价的自动化、一体化。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。